Religious people of most faiths have the tendency to say “Look at these perfect conditions for life we have on Earth, the universe was clearly made by an intelligent being for us to exist here”. But that is just not the case.
A town not far from here is Karasjok, in winter its so cold that you can easily die just a kilometer from the nearest house. If its dark (which it usually is in winter) you can get lost a hundred meters from the nearest house. If its a snowstorm you can die a hundred meters from the nearest house. In summer the only food around is some minor wildlife, fish, reindeer, and a few berries. And that’s assuming you have the tools and time to gather such food.
But there’s an entire continent that is too cold for humans to survive without specialist equipment, Antarctica:
Even if you have all the specialist equipment you need to hunt and live and not freeze to death, you still lack the fuel to cook and retain heat. Unless you burn vast quantities of oil harvested from the local wildlife (seal, whale, etc). In Karasjok at least you have some firewood.
But even places not like this can be uninhabitable, like the Himalayas:
Some areas have no fish, no firewood, no wildlife (not anything you can catch anyway), you can’t even traverse much of the terrain.
But there are also places too warm and dry for us to survive there, like the Atacama desert:
If you account for all the hostile areas where people simply don’t live today, you end up having removed over 50% the landmass of Earth from your list of potential homes.
And even if the temperature is nice and temperate and have plenty of fish, if it has no land you can’t live there, I give you for example the Atlantic Ocean:
Oceans account for 70.8% of the surface area of the Earth. Even above it where there is air to breathe you can’t really live there. Everything you need would have to be imported if you did.
But then there’s the underwater area, even just a couple feet under water you can’t survive five minutes without diving equipment:
But most of the oceans are quite deep, there you couldn’t survive a minute even in diving equipment:
That’s just about the places on Earth that will be hostile to human beings. Even the friendly places tend to be dangerous because of natural disasters like flooding, hurricanes, tornadoes, landslides, avalanches, thunderstorms, hail, etc.
Then there’s the species that are hostile to human beings.
We have polar bears, wolves, lions, sharks, even cows and rats are hostile to some extent and only kept at bay because of technology. Try standing between a hungry cow and a pile of hay, waving a gun, and the cow will run you down when its hungry enough. But these are the big stuff, these aren’t very dangerous, really. The really dangerous stuff is all the bacteria, fungi and viruses that tries to eat you or live as a parasite in/on you. Not to mention the insects and various other creepy crawlies that would eat you or kill you just to have somewhere to live, given half a chance. Even plants exist that would kill you. Even “harmless” plants like a pine tree will kill anyone it falls upon because trees aren’t soft woolly bouncy-castles made for humans to chop them down without risk.
So to summarize, over 85% of the Earth is hostile, and the lifeforms on Earth aren’t here to serve us. If you try to point at food crops and say “look these serve us”, those serve us because we have selectively decided which seeds to harvest, which to eat and which to plant. And food crops have a huge amount of predators, so humans aren’t alone in harvesting the fruits of our labor. Given half a chance insects, fungi, bacteria and other animals will eat the crops before we humans get the chance.
But then you go just 7.5 kilometers up (kilo = thousand) and then suddenly the lack of atmosphere makes sleep very difficult and digesting food becomes nearly impossible. So from Earth orbit:
If you are in the international space station you are at 408 kilometers altitude, and all the way down to about 10 kilometers is lethal. And if you look at the Earth from the moon, everything you see except a thin 10 kilometer layer on the blue marble is lethal:
And remember 85% of the blue thing is also practically lethal because you can’t live there. And you can easily get severe suffering and even serious death in the remaining habitable bit of the blue marble. Because of the life that is there. Not to mention natural disasters. Even the human body is a massive post all by itself in how many ways it is not made “for our existence”, merely for the spreading of our genes, but I cut that out because it was too graphic.
Everywhere else in the solar system is also lethal. Like for example we usually imagine Mars as a nearly habitable place:
But you would die instantly without a space suit, and slowly freeze to death even then if you can’t recharge the suit’s batteries/fuel cells from a habitat with substantial solar power resources. All these other places are also lethal. The dwarf planet Ceres:
The moon around Earth:
The moon Titan:
If we look at the volume of our solar system, it reaches out to about where the Voyager 1 spacecraft has gone. Based on the definition of how far our sun’s solar wind reaches to a certain degree. If the solar system volume is represented by the Earth you stand on, then the actual Earth can be represented by a piece of dust smaller than a grain of sand. And we can live on just 15% of the surface area of that grain of dust.
And then outside our solar system, between ours and other solar systems, is a vast emptiness with virtually no light except that which you see from the night sky. If we look at a galaxy like the Andromeda Galaxy (since we can’t take a photo of the galaxy we are in ourselves):
Then we represent our galaxy by imagining that it is really the size of our solar system, then our solar system is that grain of dust from earlier. And in that grain of dust is an atom that represents the Earth, and around that atom there is a single layer of electrons that represent the surface of the Earth, and we can live on 15% of that surface.
Then keep in mind that most dots on this picture is another galaxy.
The universe is more than 99.99999999999999999999999999999999999999999999999999999999999999% lethal to human beings.
So why are we here? Because of the sun vast amounts of energy hits our planet, and because of many coincidences this energy resulted in self-replicating molecules. And eventually because of chance, a technological species came into being. And this technological being now has the capacity, for the first time ever, to use scientific knowledge to intervene in the aging processes. And in doing so live in good health and youth forever. Long enough to save up for our own personal spacecrafts, and then set up mining on Ceres and the moon and asteroids. And then using the stuff we gather we can spread out into the vast deadliness of space.
But why do so? To survive the end of this deadly universe, in spite of its deadliness. How do we do this? That is what I explain in my book.